Studentroom

Phospholipid bilayers are NOT stabilised by: a. van der Walls forces b. covalent bonds c. hydrogen bonds d. ionic bonds e. hydrophobic interactions - b. covalent bonds A transmembrane protein has the following properties: it has two binding sites, one for solute A and one for solute B. The protein can undergo a conformational change to switch between two states: either both binding sites are exposed exclusively on one side of the membrane, or both are exposed exclusively on the ot...

Phospholipid bilayers are NOT stabilised by: a. van der Walls forces b. covalent bonds c. hydrogen bonds d. ionic bonds e. hydrophobic interactions - b. covalent bonds A transmembrane protein has the following properties: it has two binding sites, one for solute A and one for solute B. The protein can undergo a conformational change to switch between two states: either both binding sites are exposed exclusively on one side of the membrane, or both are exposed exclusively on the ot...

Phospholipid bilayers are NOT stabilised by: a. van der Walls forces b. covalent bonds c. hydrogen bonds d. ionic bonds e. hydrophobic interactions - b. covalent bonds A transmembrane protein has the following properties: it has two binding sites, one for solute A and one for solute B. The protein can undergo a conformational change to switch between two states: either both binding sites are exposed exclusively on one side of the membrane, or both are exposed exclusively on the ot...

DNA that encodes information for proteins is within the ________ - nucleus What makes up the transcription complex that transcribes DNA? - Polymerases and transcription factors Transcriptional complexes transcribe DNA into _______ - mRNA ________________ machinery reads mRNA after it has been shuttled into the cytoplasm - translational Where are ribosomes formed? - nucleus ______________ make up the translational machinery that reads mRNA - Ribosomes The amino acid chain that forms the p...

Question 1. What is modern cell biology? - An integrated discipline that includes cell culture, microscopy, molecular biology, genetics, and biochemistry. Question 2. What is gene ontology? - A major bioinformatics initiative to unify the representation of gene and gene product (i.e. proteins and RNA) attributes. The project includes development of a controlled vocabulary of a protein's attributes. Question 3. What are the three domains of gene ontology? Briefly describe them. - Cellular ...

A fish is excreting large volumes of water; we would describe it as ______________________ relative to its environment. - An osmoregulator that is hyperosmotic. Which of the following animals likely makes the most nitrogenous waste? A. Frugivorous Bat B. Insectivorous Frog C. Piscivorous Seal D. Granivorous Bird - C. Piscivorous Seal Which of the following statements about mammalian excretion if FALSE: A. Substances like solutes always diffuse across the nephron membrane, with direction ...

Which of the following transport mechanisms may be utilized to move glucose across cell membranes? - Secondary active transport and facilitated diffusion Which of the following statements about the Na-K pump is(are) true? - The location of the binding sites on the Na-K pump dictates the direction of solute movement. Examples of active transport may include __________. - the movement of Na+ ions out of cells and the movement of glucose molecules into intestinal epithelial cells Which of the...

What is the goal of bioremediation? - To clean up areas polluted with toxic compounds using bacteria Broad-spectrum antibiotics inhibit the growth of most intestinal bacteria. Consequently, assuming that nothing is done to counter the reduction of intestinal bacteria, a hospital patient who is receiving broadspectrum antibiotics is most likely to become - deficient in certain vitamins and nutrients If prokaryotes did not exist, what would change in the nitrogen cycle? - The rate of movement ...

Which of the following is a major difference between prokaryotic and eukaryotic cells? - Eukaryotic cells have organelles and prokaryotes do not Which of the following are found in prokaryotes? Chloroplasts, mitochondria, a chromosome, ribosomes - Chromosomes and ribosomes What is the main function of the enzymes found in a eukaryotic cell's lysosome? - Breaking down macromolecules into smaller parts What is the main function of the enzymes found in the smooth endoplasmic reticulum of euk...

The ecology of algae in aquatic ecosystems parallels that of plants in terrestrial ecosystems. Make three points to support this statement. - Aglae and mosses/plants have similar features such as: - branched apical growth - cuticles - asymmetrical flagellated cells - cellulose, thylakoids, chlorophyll b, some have 2 flagella... If some Euglenoids have the same pigment as green algae and higher plants, why are they not so closely related? - secondary endosymbiosis Why evolve towards a s...

What kinds of membranous structures can be seen on electron micrographs of the cell interior? - Vesicles, network of membrane-bound channels, stacks of flattened, membrane-bound sacs (e.g. golgi apparatus, RER) What pathways of vesicle trafficking through the cytoplasm have been discovered? - motor proteins pull vesicles along tracks of microtubules and microfilaments What substances of the biosynthetic pathway are made in the Golgi apparatus? - lipids and carbohydrates What is the synthe...

If a human has a serious bacterial infection, which bacterial target or targets could be useful targets when designing bacterial antibiotics? a. 40S ribosomal subunits b. gyrase c. a peptidoglycan biosynthesis enzyme d. B and C e. A, B and C - d. B and C (gyrase, a peptidoglycan biosynthesis enzyme) With regards to modern medicine, pathogenicity and pharmacology, it is very important that one understand one fundamental concept. That concept is that researchers will look for and attack en...

Definition of Evolution (Darwin's time): - Descent with modification. Definition of Evolution (currently): - A change in the genetic composition of a population from generation to generation. Descent with modification: - A phrase Darwin used in proposing that Earth's many species are descendants of ancestral species that were different from the present-day species. 1) Which of the following statements best describes theories? A) They are nearly the same things as hypotheses. B) They are...

Lamarck's ideas about_____ have been soundly rejected. - How adaptation occurs Darwin's mechanism for the cause of evolution was based upon... - Characteristics that enhance survival are heritable &Existing variation among individuals What accounts for broad, continuous variation of a particular phenotype within a population. - Multiple genes Select the true statement from those listed below. The evolution of larger genome size is expanded by gene duplication events When a point mutati...

What is the D configuration of a sugar in a Fisher projection? - chyrol carbon furthest from the carboxyl group hydroxyl on right What is the L configuration of a sugar in a Fisher projection? - hydroxyl on left What is the difference between glycogen and amylopectin? - glycogen- has branches about every 10 residues (more highly branched) amylopectin- has branches about every 25 What is amylose made up of? - glucose What makes up starch? - amylose amlyopectin What is a glycosidic bond?...

Deedra's dad has Alzheimer's Disease (AD) which is caused by a change in protein structure - True Alzheimer's disease is caused by aggregation of the Amyloid beta peptide and tangle formation by the tau protein. What kinds of amino acids are likely to drive the formation of these protein aggregates? - hydrophobic After learning about Alzheimer's disease and one of the drugs used in its treatment, what other drug design strategies could you use to offer treatment for AD? - 1. Drugs tha...

What vitamin does not travel through the bloodstream in the form of a lipid micelle? - Vitamin C Which lipid has a 4-ring structure? - Sterol Which of the following situations is MOST likely to increase the rate of beta oxidation? - fasting A patient who is on a no-fat diet is at particular risk of deficiency in: - Vitamin A During starvation, triglycerides can help supply some of the body's glucose needs. Which breakdown product of triglycerides can be used to make glucose? - glycerol CH...

The polysaccharide cellulose is composed of sugar monomers linked through beta linkages, with their CH2OH groups in opposite direction relative to the neighboring monomer. - True Nutrient that can not be broken down to a substance that can participate in the production of ATP via aerobic cellular metabolism - Vitamin E Glycolysis produces 2 ATP molecules, through what process are these ATP molecules made? - Substrate level phosphorylation What product of beta oxidation is able to enter the...

Each of the following subcellular structures contains DNA EXCEPT A. the nucleus. B. ribosomes. C. chloroplasts. D. mitochondria. - B In plant and animal cells, the three-dimensional integrity of the cell is maintained, in part, by an internal network of filaments called A. the cell wall. B. the Golgi apparatus. C. the cytoskeleton. D. the endoplasmic reticulum. - C Of the following, which are prokaryotes? A. viruses B. bacteria C. yeast D. plant cells - B G° for the conversion o...

What amino acids have nonpolar, aliphatic R groups? - Glycine, Alanine, Proline, Valine, Leucine, Isoleucine, Methionine What amino acids have polar, uncharged R groups? - Serine, Threonine, Cysteine, Asparagine, and Glutamine What amino acids have aromatic R groups? - Phenylalanine, Tyrosine, and Tryptophan What amino acids have negatively charged R groups? - Aspartate and Glutamate What amino acids have positively charged R groups? - Lysine, Arginine, and Histidine What is isoelectric f...